Justin reciprocated the compliment, saying of watching back their nude scenes, "I love watching Mila in the movie, doesn't bother me at all."

But as for watching his own tush on-screen? "Not so much," dished the pop star.

Turns out Mila, too, has somewhat of a complex about watching herself on the big screen.

"I am incredibly self-conscious in real life about every part of my body," revealed the skinny minny actress. "Let alone for the whole crew to see and the whole world to see—the last person I cared about was him!" Mila exclaimed, referring to her co-star, JT.

Yeah, yeah, that's 'cause the dude would have been happy to see anything Mila was showin'! But luckily, the costars had four months of getting to know each other before having to drop trou.

"It was a little less awkward for us because the request was to make the scenes funny as possible," dished Justin. "We were more going for laughs, so that helped break the ice."

Putting each other at ease with the edgy humor is something these two do very comfortably, so even if Mila and Justin aren't exes, they sure do act like it!